what kind of substrate ?????

chelseabrn1 · Oct 4, 2013

I work at a pet store that carries salt water fish. I have recently been promoted to manage that aquatic section of the store. The previous person that left this position has left the salt water tanks in shambles. I have nitrates around 160 and my systems keep getting ich. I have been doing the weekly gravel vacing and water changes in these tanks for 3 months and I am still getting nowhere with the high nitrates. I think the problem is the substrate that is in my systems. The fish only system has a very very thin layer of course crushed coral, with a small piece of live rock in each tank. The system in run of a sump with a protein skimmer and 2 bio wheels. I believe that because the substrate is so think and course that there is nowhere for anaerobic bacteria to live to convert the nitrates into nitrogen gas. ideally I would like to remove all the substrate but that is against the companies policies. so I want to change the substrate to a finer material with a thicker bed. But I cannot use sand because I also have to do a gravel vac once a week because that is in policy also. please help I need some advice

Mike J. · Oct 4, 2013

Well, if you're not going to have any natural biological filtration, like lots of like rock or deep sand bed, have you thought about a sump with bio balls? I would recommend 25 - 50 percent water changes weekly. Unless that's against store policy too.

On second thought I know of a fish store that runs a large bio pellet reactor with success.

skinz78 · Oct 4, 2013

Welcome to Reef2Reef!

Personally I would get some of this stuff, you can still vac it, it's what I use in my reef.

aragonite

mcarroll · Oct 4, 2013

Do what you have to in the displays, just make it as easy and quick to keep clean as you can. I might even get plain river gravel just because it vacuums clean quickly.

For complete denitrification, some live rock is your best bet IMO. Around 1 lb. per gallon of system water.

One or more chunks in each display - just a little so it can be moved and cleaned around easily, and doesn't become another thing for fish to hide inside - and the balance in the sump. Keep it dark in the sump to minimize maintenance requirements and don't hesitate to pull the rock out occasionally to vacuum out the detritus that will inevitably collect. A small (dedicated) shop vac can make easy work of this.

Good luck!

-Matt